Saliva testing as a means to monitor therapeutic lithium levels in patients with psychiatric disorders: Identification of clinical and environmental covariates, and their incorporation into a prediction model.
Bipolar Disord
; 23(7): 679-688, 2021 11.
Article
en En
| MEDLINE
| ID: mdl-34536974
OBJECTIVE: The narrow therapeutic window of lithium medications necessitates frequent serum monitoring, which can be expensive and inconvenient for the patient. Compared to blood, saliva collection is easier, non-invasive, requires less processing, and can be done without the need for trained personnel. This study investigated the utility of longitudinal salivary lithium level monitoring. METHODS: We measured salivary lithium levels using ICP-OES in n = 169 passive drool samples, collected both as single observations and longitudinally for up to 18 months, from a multi-center cohort of n = 75 patients with bipolar disorder or other psychiatric conditions. RESULTS: Saliva and serum lithium levels were highly correlated. Adjustment for daily lithium dose, diabetes, and smoking improved this relationship (r = 0.77). Using the adjusted intersubject equation and a patient's salivary lithium value, we observed a strong correlation between the predicted vs. observed serum lithium levels (r = 0.70). Most patients had highly stable saliva/serum ratios across multiple visits, with longitudinal variability significantly greater with age. Use of the intrasubject saliva/serum ratio from a single prior observation had similar predictive power to the use of the adjusted intersubject equation. However, the use of the mean intrasubject ratio from three prior observations could robustly predict serum lithium levels (predicted vs. observed r = 0.90). CONCLUSIONS: These findings strongly suggest that saliva could be used for lithium monitoring, and open the door for the development and implementation of a point-of-care salivary lithium device for use at home or the clinic. We propose that the use of saliva will dramatically improve treatment opportunities for patients with mood disorders.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Trastorno Bipolar
/
Trastornos Mentales
Tipo de estudio:
Clinical_trials
/
Diagnostic_studies
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Prognostic_studies
/
Risk_factors_studies
Límite:
Humans
Idioma:
En
Revista:
Bipolar Disord
Asunto de la revista:
PSIQUIATRIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Dinamarca